1. The Effect of Sense Manipulation on Postural Stability By: Kyle Bohnert and Rachael Moreland Hanover College

2. Posture Body thought of as an inverted pendulum –Very Unstable –Small area of support in which the COM must fall Posture –Considered to be a dynamic

3. Posture Cont. There are three main sensory inputs that help control posture –Vestibular –Visual –Somatosensory

4. Somatosensory System. http://www.thestretchinghandbook.com/archives/myotatic-stretch-reflex.php

5. Vestibular System www.humanneurophysiology.com

6. Visual System

7. Research Question We are interested in discovering what will happen with posture when more of our senses become impaired

8. Participants Hanover College Students –13 Participants Males = 6 Females = 7 Age range = 18-22 –Average = 20 –No known postural deficits, visual defects beyond that which can be fixed by glasses, vestibular or somatosensory defects

9. Room/Equipment

10. Protocol 2 X 2 X 2 Study Somatosensory YES NO VISION VISION YES NO YES NO YES VESTIBULAR NO YYYYNY YYNYNN NYYNNY NYNNNN

11. Overall Standard Deviation P = 0.066

12. Levels of Sway Frequency

13. Control FFT

14. Results Low Frequency (0.5-1.5HZ) F(1,11)=1.00 P < 0.05

15. Results High Frequency (4.25-4.75HZ) F(1,11)=4.785 P < 0.05

16. Discussion Low Frequency Main effect for spin After spinning, the fluid in the semi circular canals provides false information –Sense of continual motion –3 possible explanations Effected by rate at which spun The way vestibular system works Optimal frequency for vestibular.

17. Discussion High Frequency Main effect for vision –Participants swayed less with eyes closed than with eyes open. Similar to results seen by Kinsella Shaw (2006) However just seen in high frequency –Visual Fixation Task (Stoffregen, 2007) –Sway less = more at high frequency

18. Discussions Limitations –Number of participants. –Randomizing the order of icing and spinning conditions. –Diverse group Age range Athletes vs Non-Athletes

19. Questions?